[摘 要] 本文研究了用電壓矢量變頻器和感應(yīng)電動(dòng)機(jī)構(gòu)成的變頻電動(dòng)機(jī)系統(tǒng)。通過對(duì)該閉環(huán)控制系統(tǒng)數(shù)學(xué)模型的建立,推導(dǎo)出了它的傳遞函數(shù)。它有著與可控硅直流調(diào)速系統(tǒng)極其相似的傳遞函數(shù),因而可用直流電動(dòng)機(jī)的閉環(huán)控制對(duì)該系統(tǒng)加以控制。通過實(shí)際的測(cè)試,得到比較滿意的結(jié)果。
[關(guān)鍵詞] 感應(yīng)電動(dòng)機(jī);變頻器;傳遞函數(shù);閉環(huán)控制
Abstract: In this paper, we present a frequency conversion electromotor system organized by voltage vector transducer and induction-motor. We export the transfer-function of the close-loop control system by establishing its mathematic model. Because of the surprising similitude of the transfer-functions of the close-loop control system and the controllable silicon timing system, we can control the system using the close-loop control of DC electromotor. We also obtain satisfied result by actual testing.
Keywords: induction-motor, transducer, transfer-function, close-loop control
1. 引言
感應(yīng)電動(dòng)機(jī)的數(shù)學(xué)模型是一個(gè)高階非線性強(qiáng)耦合的多變量系統(tǒng)。為了提高感應(yīng)電動(dòng)機(jī)的靜、動(dòng)態(tài)性能,將變頻器和感應(yīng)電動(dòng)機(jī)構(gòu)成感應(yīng)電動(dòng)機(jī)系統(tǒng),采用閉環(huán)控制,以達(dá)到此目的[1]。采用的變頻器為電感矢量控制PWM變頻器,它是從電動(dòng)機(jī)轉(zhuǎn)矩直接控制的角度出發(fā),以三相對(duì)稱電壓供電,建立電動(dòng)機(jī)定子理想磁鏈為基準(zhǔn),由三相逆變器不同開關(guān)模式供電給感應(yīng)電動(dòng)機(jī),產(chǎn)生實(shí)際磁鏈跟蹤基準(zhǔn)磁鏈來決定變頻器的開關(guān)模式,從而形成PWM波[2],這樣可以將感應(yīng)電動(dòng)機(jī)的強(qiáng)耦合得到近似解耦,在忽略旋轉(zhuǎn)電壓的影響,并認(rèn)為非線性關(guān)系都可按線性化處理,這樣得到的變頻器感應(yīng)電動(dòng)機(jī)系統(tǒng)和直流電動(dòng)機(jī)的數(shù)學(xué)模型極為相似,故可采用直流調(diào)速系統(tǒng)已經(jīng)比較成熟的工程設(shè)計(jì)法對(duì)該系統(tǒng)加以控制,以提高該系統(tǒng)的靜、動(dòng)態(tài)性能。
詳情請(qǐng)點(diǎn)擊:
感應(yīng)電動(dòng)機(jī)的閉環(huán)控制系統(tǒng)設(shè)計(jì)